I've created a private server using minecraft_server.1.8.1 . We've been playing Minecraft normally for a couple of weeks. However yesterday the server stopped working. When I double-click on it, it flashes, but shuts down immediately. I can't figure out what's wrong. I couldn't find the solution on this page nor anywhere else, so I'm posting the crash file in hope you might be able to help me. My attemps at the solution were so far:
-checking if the EULA is confirmed (set to "true")
-redownloading the server file and put it in new folder. it does the same as the old file, doesn't launch.
-updated Java to the latest version
-Checked that the server file is added to the exceptions of windows firewall
-checked that watcdog setting (I forgot how's it called), it is set to 60000

This is the crash report:
---- Minecraft Crash Report ----
// You're mean.

Time: 31.12.2014 16:28
Description: Watching Server

java.lang.Error
at boy.a(SourceFile:196)
at bpn.a(SourceFile:40)
at bpn.a(SourceFile:19)
at bpf.a(SourceFile:17)
at bpi.a(SourceFile:15)
at bpg.a(SourceFile:25)
at arw.a(SourceFile:112)
at bgt.a(SourceFile:108)
at bgt.d(SourceFile:201)
at qt.c(SourceFile:87)
at qt.d(SourceFile:116)
at aqr.a(SourceFile:276)
at aqr.f(SourceFile:272)
at aqr.p(SourceFile:657)
at awk.b(SourceFile:66)
at ato.a(SourceFile:445)
at qu.h(SourceFile:383)
at qu.c(SourceFile:202)
at net.minecraft.server.MinecraftServer.A(SourceFile:600)
at pp.A(SourceFile:299)
at net.minecraft.server.MinecraftServer.z(SourceFile:532)
at net.minecraft.server.MinecraftServer.run(SourceFile:448)
at java.lang.Thread.run(Unknown Source)

A detailed walkthrough of the error, its code path and all known details is as follows:
---------------------------------------------------------------------------------------

– Head –
Stacktrace:
at boy.a(SourceFile:196)
at bpn.a(SourceFile:40)
at bpn.a(SourceFile:19)
at bpf.a(SourceFile:17)
at bpi.a(SourceFile:15)
at bpg.a(SourceFile:25)
at arw.a(SourceFile:112)
at bgt.a(SourceFile:108)
at bgt.d(SourceFile:201)
at qt.c(SourceFile:87)
at qt.d(SourceFile:116)
at aqr.a(SourceFile:276)
at aqr.f(SourceFile:272)
at aqr.p(SourceFile:657)
at awk.b(SourceFile:66)
at ato.a(SourceFile:445)
at qu.h(SourceFile:383)
at qu.c(SourceFile:202)
at net.minecraft.server.MinecraftServer.A(SourceFile:600)
at pp.A(SourceFile:299)
at net.minecraft.server.MinecraftServer.z(SourceFile:532)

– Thread Dump –
Details:
Threads: "Netty Server IO #5" Id=30 RUNNABLE
at sun.nio.ch.WindowsSelectorImpl$SubSelector.poll0(Native Method)
at sun.nio.ch.WindowsSelectorImpl$SubSelector.poll(Unknown Source)
at sun.nio.ch.WindowsSelectorImpl$SubSelector.access$400(Unknown Source)
at sun.nio.ch.WindowsSelectorImpl.doSelect(Unknown Source)
at sun.nio.ch.SelectorImpl.lockAndDoSelect(Unknown Source)

• locked io.netty.channel.nio.SelectedSelectionKeySet@9ec512
• locked java.util.Collections$UnmodifiableSet@19c37a0
• locked sun.nio.ch.WindowsSelectorImpl@1082091
  at sun.nio.ch.SelectorImpl.select(Unknown Source)
  at io.netty.channel.nio.NioEventLoop.select(NioEventLoop.java:622)
  at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:310)
  ...

"Netty Server IO #4" Id=29 RUNNABLE (in native)
at sun.nio.ch.WindowsSelectorImpl$SubSelector.poll0(Native Method)
at sun.nio.ch.WindowsSelectorImpl$SubSelector.poll(Unknown Source)
at sun.nio.ch.WindowsSelectorImpl$SubSelector.access$400(Unknown Source)
at sun.nio.ch.WindowsSelectorImpl.doSelect(Unknown Source)
at sun.nio.ch.SelectorImpl.lockAndDoSelect(Unknown Source)

• locked io.netty.channel.nio.SelectedSelectionKeySet@923f4e
• locked java.util.Collections$UnmodifiableSet@17a3b00
• locked sun.nio.ch.WindowsSelectorImpl@1b79e95
  at sun.nio.ch.SelectorImpl.select(Unknown Source)
  at io.netty.channel.nio.NioEventLoop.select(NioEventLoop.java:622)
  at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:310)
  ...

"Netty Server IO #3" Id=28 RUNNABLE (in native)
at sun.nio.ch.WindowsSelectorImpl$SubSelector.poll0(Native Method)
at sun.nio.ch.WindowsSelectorImpl$SubSelector.poll(Unknown Source)
at sun.nio.ch.WindowsSelectorImpl$SubSelector.access$400(Unknown Source)
at sun.nio.ch.WindowsSelectorImpl.doSelect(Unknown Source)
at sun.nio.ch.SelectorImpl.lockAndDoSelect(Unknown Source)

• locked io.netty.channel.nio.SelectedSelectionKeySet@c68e1
• locked java.util.Collections$UnmodifiableSet@b9a46b
• locked sun.nio.ch.WindowsSelectorImpl@1d9adcc
  at sun.nio.ch.SelectorImpl.select(Unknown Source)
  at io.netty.channel.nio.NioEventLoop.select(NioEventLoop.java:622)
  at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:310)
  ...

"Netty Server IO #2" Id=27 RUNNABLE (in native)
at sun.nio.ch.WindowsSelectorImpl$SubSelector.poll0(Native Method)
at sun.nio.ch.WindowsSelectorImpl$SubSelector.poll(Unknown Source)
at sun.nio.ch.WindowsSelectorImpl$SubSelector.access$400(Unknown Source)
at sun.nio.ch.WindowsSelectorImpl.doSelect(Unknown Source)
at sun.nio.ch.SelectorImpl.lockAndDoSelect(Unknown Source)

• locked io.netty.channel.nio.SelectedSelectionKeySet@215402
• locked java.util.Collections$UnmodifiableSet@12568d
• locked sun.nio.ch.WindowsSelectorImpl@1f05a9c
  at sun.nio.ch.SelectorImpl.select(Unknown Source)
  at io.netty.channel.nio.NioEventLoop.select(NioEventLoop.java:622)
  at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:310)
  ...

"Netty Server IO #1" Id=26 RUNNABLE (in native)
at sun.nio.ch.WindowsSelectorImpl$SubSelector.poll0(Native Method)
at sun.nio.ch.WindowsSelectorImpl$SubSelector.poll(Unknown Source)
at sun.nio.ch.WindowsSelectorImpl$SubSelector.access$400(Unknown Source)
at sun.nio.ch.WindowsSelectorImpl.doSelect(Unknown Source)
at sun.nio.ch.SelectorImpl.lockAndDoSelect(Unknown Source)

• locked io.netty.channel.nio.SelectedSelectionKeySet@ccd36e
• locked java.util.Collections$UnmodifiableSet@14cf6dd
• locked sun.nio.ch.WindowsSelectorImpl@1e348a9
  at sun.nio.ch.SelectorImpl.select(Unknown Source)
  at io.netty.channel.nio.NioEventLoop.select(NioEventLoop.java:622)
  at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:310)
  ...

"File IO Thread" Id=36 RUNNABLE
at java.io.RandomAccessFile.writeBytes0(Native Method)
at java.io.RandomAccessFile.writeBytes(Unknown Source)
at java.io.RandomAccessFile.write(Unknown Source)
at bft.a(SourceFile:318)
at bft.a(SourceFile:255)

• locked bft@b761a7
  at bfu.close(SourceFile:236)
  at java.util.zip.DeflaterOutputStream.close(Unknown Source)
  at java.io.FilterOutputStream.close(Unknown Source)
  ...

"Server Watchdog" Id=34 RUNNABLE
at sun.management.ThreadImpl.dumpThreads0(Native Method)
at sun.management.ThreadImpl.dumpAllThreads(Unknown Source)
at pu.run(SourceFile:43)
at java.lang.Thread.run(Unknown Source)

"Netty Server IO #0" Id=25 RUNNABLE (in native)
at sun.nio.ch.WindowsSelectorImpl$SubSelector.poll0(Native Method)
at sun.nio.ch.WindowsSelectorImpl$SubSelector.poll(Unknown Source)
at sun.nio.ch.WindowsSelectorImpl$SubSelector.access$400(Unknown Source)
at sun.nio.ch.WindowsSelectorImpl.doSelect(Unknown Source)
at sun.nio.ch.SelectorImpl.lockAndDoSelect(Unknown Source)

• locked io.netty.channel.nio.SelectedSelectionKeySet@16c2ab2
• locked java.util.Collections$UnmodifiableSet@671928
• locked sun.nio.ch.WindowsSelectorImpl@a49774
  at sun.nio.ch.SelectorImpl.select(Unknown Source)
  at io.netty.channel.nio.NioEventLoop.select(NioEventLoop.java:622)
  at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:310)
  ...

"DestroyJavaVM" Id=22 RUNNABLE

"Server thread" Id=20 RUNNABLE
at boy.a(SourceFile:196)
at bpn.a(SourceFile:40)
at bpn.a(SourceFile:19)
at bpf.a(SourceFile:17)
at bpi.a(SourceFile:15)
at bpg.a(SourceFile:25)
at arw.a(SourceFile:112)
at bgt.a(SourceFile:108)
...

"TimerQueue" Id=18 TIMED_WAITING on java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject@14251eb
at sun.misc.Unsafe.park(Native Method)

• waiting on java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject@14251eb
  at java.util.concurrent.locks.LockSupport.parkNanos(Unknown Source)
  at java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.awaitNanos(Unknown Source)
  at java.util.concurrent.DelayQueue.take(Unknown Source)
  at javax.swing.TimerQueue.run(Unknown Source)
  at java.lang.Thread.run(Unknown Source)

Number of locked synchronizers = 1

• java.util.concurrent.locks.ReentrantLock$NonfairSync@1d363e1

"AWT-EventQueue-0" Id=16 WAITING on java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject@11042ed
at sun.misc.Unsafe.park(Native Method)

• waiting on java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject@11042ed
  at java.util.concurrent.locks.LockSupport.park(Unknown Source)
  at java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(Unknown Source)
  at java.awt.EventQueue.getNextEvent(Unknown Source)
  at java.awt.EventDispatchThread.pumpOneEventForFilters(Unknown Source)
  at java.awt.EventDispatchThread.pumpEventsForFilter(Unknown Source)
  at java.awt.EventDispatchThread.pumpEventsForHierarchy(Unknown Source)
  at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
  ...

"AWT-Windows" Id=14 RUNNABLE (in native)
at sun.awt.windows.WToolkit.eventLoop(Native Method)
at sun.awt.windows.WToolkit.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)

"AWT-Shutdown" Id=13 WAITING on java.lang.Object@99f4ec
at java.lang.Object.wait(Native Method)

• waiting on java.lang.Object@99f4ec
  at java.lang.Object.wait(Object.java:503)
  at sun.awt.AWTAutoShutdown.run(Unknown Source)
  at java.lang.Thread.run(Unknown Source)

"Java2D Disposer" Id=12 WAITING on java.lang.ref.ReferenceQueue$Lock@19eeec8
at java.lang.Object.wait(Native Method)

• waiting on java.lang.ref.ReferenceQueue$Lock@19eeec8
  at java.lang.ref.ReferenceQueue.remove(Unknown Source)
  at java.lang.ref.ReferenceQueue.remove(Unknown Source)
  at sun.java2d.Disposer.run(Unknown Source)
  at java.lang.Thread.run(Unknown Source)

"Server Infinisleeper" Id=11 TIMED_WAITING
at java.lang.Thread.sleep(Native Method)
at pq.run(SourceFile:65)

"Snooper Timer" Id=10 TIMED_WAITING on java.util.TaskQueue@14ec8cc
at java.lang.Object.wait(Native Method)

• waiting on java.util.TaskQueue@14ec8cc
  at java.util.TimerThread.mainLoop(Unknown Source)
  at java.util.TimerThread.run(Unknown Source)

"Attach Listener" Id=5 RUNNABLE

"Signal Dispatcher" Id=4 RUNNABLE

"Finalizer" Id=3 WAITING on java.lang.ref.ReferenceQueue$Lock@160d401
at java.lang.Object.wait(Native Method)

• waiting on java.lang.ref.ReferenceQueue$Lock@160d401
  at java.lang.ref.ReferenceQueue.remove(Unknown Source)
  at java.lang.ref.ReferenceQueue.remove(Unknown Source)
  at java.lang.ref.Finalizer$FinalizerThread.run(Unknown Source)

"Reference Handler" Id=2 WAITING on java.lang.ref.Reference$Lock@1fec2ad
at java.lang.Object.wait(Native Method)

• waiting on java.lang.ref.Reference$Lock@1fec2ad
  at java.lang.Object.wait(Object.java:503)
  at java.lang.ref.Reference$ReferenceHandler.run(Unknown Source)

Stacktrace:
at pu.run(SourceFile:59)
at java.lang.Thread.run(Unknown Source)

– System Details –
Details:
Minecraft Version: 1.8.1
Operating System: Windows 7 (x86) version 6.1
Java Version: 1.7.0_67, Oracle Corporation
Java VM Version: Java HotSpot(TM) Client VM (mixed mode), Oracle Corporation
Memory: 347409416 bytes (331 MB) / 519110656 bytes (495 MB) up to 1037959168 bytes (989 MB)
JVM Flags: 2 total; -Xms512m -Xmx1024m
IntCache: cache: 0, tcache: 0, allocated: 13, tallocated: 95
Profiler Position: N/A (disabled)
Player Count: 2 / 20; [qx['katka01'/9071, l='world', x=58,69, y=47,00, z=56,57], qx['HRCO'/8833, l='world', x=-72,43, y=71,00, z=80,57]]
Is Modded: Unknown (can't tell)
Type: Dedicated Server (map_server.txt)